


UnderHell: Genisys

by IlloustriousTaco



Series: UnderHell [2]
Category: Undertale (Video Game)
Genre: Bad Psuedo Science, Canonical Character Death, Gen, How Do I Tag, I Don't Even Know, Kinda, Minor Violence, Sad, This Is Why We Can't Have Nice Things
Language: English
Status: Completed
Published: 2016-04-25
Updated: 2016-04-25
Packaged: 2018-06-04 13:18:07
Rating: Not Rated
Warnings: Major Character Death
Chapters: 1
Words: 2,187
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/6659653
Author URL: https://archiveofourown.org/users/IlloustriousTaco/pseuds/IlloustriousTaco
Summary: <blockquote class="userstuff">
              <p>The Act of Creation is a beautiful thing. </p>
<p>Until Gaster gets involved. </p>
<p>An UnderHell backstory.</p>
            </blockquote>





	UnderHell: Genisys

**Author's Note:**

> WARNING: This is an UnderHell story, and in UnderHell it really is Kill or be killed. 
> 
> That being said, Gaster is a bit of a Dink in this. I've seen many portrayals of him that I like, and this definitely falls on the sadistic side of morality. Like seriously, his moral compass is screwed. I actually wrote this before the rest of UnderHell, so it explains a bit about Sans and why he thinks the way he does and reacts the way he does to certain things, and later that will explain a few things about Papyrus as well.

The experiments were all failures, even with access to an unexpired human and a human soul to draw power from. It seemed that every creature made from the core magic and as close as it was possible to get to the power level he needed for his experiments without using real monsters of the highest calibers, was still unable to handle the injections of human soul magic Gaster was using. It was hard finding the proper non destructive motions to express his pique at the situation, being limited to speaking in hands by the wounds he had sustained in the war, but Gaster made due as he flushed the test tubes clean to start a fresh batch.

Monster skeletons were much sturdier, and more expressive, than the skeletons Gaster had discovered within the squishy meat shell of a human carapace, and Gaster took advantage of that in his experiments. He needed something _more_ if he was going to be able to conduct the experiments with Determination he needed. Surely if they could measure and use that most mysterious of human magics, it would be easy to take down the barrier and get revenge for the atrocities the humans had committed upon them.

Shorter lived monster lineages couldn't even remember that humans had souls in the above world, and that the creatures given to the underground to torment and kill the monster race were aberrations instead of the natural course of things. The human carapace writhing on the surgery table, strapped safely down and gagged, was empty of soul and drained of magic. What remained was anger and pain, and the poor thing had probably even been driven to it not of it's own will.

Gaster carefully detached that thought from his scientific study and gave a little more consideration to the creature strapped safely down. Dust coated it's hands and clothing, and Gaster hadn't bothered to clean it up.

Perhaps he was going about this the wrong way.

Pondering alternative possibilities, Gaster took a sample of the fluid that leaked from cuts and scrapes in the humans outer shell, sliding it under a microscope and scanning it with his magic. It didn't take him long to determine that the instructions for how to build a fresh human were coded into the solid bits within the liquid. Oh not all of them, but the ones Gaster could read were complete enough, and he felt his skeletal grin widen as he realized that he could fill in the gaps with his own life codes, to create something more than a monster or a mere human, perhaps strong enough to act as a vessel for the Determination he needed in his experiments.

When the first try didn't immediately melt, Gaster knew he was on the right track. It didn't last long, but he got more of the data he needed to fine tune the variables. Soon he would have a weapon capable of taking down the Barrier and keeping Monsterkind safe from the depredations of humans.

Hundreds of tries and nearly a decade later, the first surviving prototype was ready to be pulled out of the tube. The human carapace had ceased functioning and been returned to the King for his own purposes long ago, and the precious soul, a vast boost of power that any monster could seize if Gaster wasn't so very careful, was under tight lock down. Taking the Determination out didn't seem to cause any damage to the Soul, which Gaster found himself rather thankful for. It would have been disappointing to have used up a finite resource while trying to make something to break the Barrier.

Using magic to scan the prototype, Gaster frowned. The power contained in the small, skeletal form so similar to his own extinct subspecies was off the charts. It seemed that the key was using barely any of the human life codes spliced into his own and infusing it with the magic from the Core so it would grow as if it was a young monster. The disappointment came when Gaster realized that the creature had zero defense, and no matter which health scale he used it barely came up to one.

Checking his charts, Gaster confirmed that a healthy monster child of the same 'age' as his creation would have at least a fifteen on the health scale, or fifteen health points. Infants normally started out with at least five, and while monster race, EXP and LV all influenced the final health point count, it was fairly consistent across the board for children. If a healer discovered that a child had only one maximum health point, they would inform the parents that it would be a good idea to say their goodbyes and set affairs in order.

In the kill or be killed world of the underground, such low health was a certain death sentence.

Gaster nearly aborted the experiment right then in disappointment, but held back as it began to awaken. The power in the small form was an intriguing counter to the nearly non existent health and perhaps it was a trade off of some kind. Gaster would need to do more research on the twisted humans, find out what average health points looked like for one of them, preferably before they acquired enough EXP and LV to skew the results.

Gaster looked down to where the experiment had awakened and was beginning to cry. It took a considerable amount of magic to tether it to the table surface so that it wouldn't damage itself while Gaster started the next batch. Even if this one survived long enough to be useful, it wouldn't hurt to have a backup plan. And with a little fiddling Gaster was certain he could find a way to keep the improved power without sacrificing durability.

* * *

It spoke in hands, perhaps picking up on Gaster's own language as it observed him. Gaster found it's mind fascinating, and even as it learned to 'speak', it showed intuitive leaps and bounds in reasoning that left Gaster reeling. Between testing its power, which he had to invent new charts for weekly it seemed since it's strength was still growing, and testing its other attributes, Gaster had taken to teaching it his own work.

It was like having a competent lab assistant.

Gaster was careful not to take his frustration out on the fragile creature though. It had been another fruitless decade, even with studying the fresh soulless carapace that had come down not long after the experiment awakened. None of the new experiments, meant to be an upgrade from the first, had survived long enough to decant from the test tubes. It was infuriatingly frustrating.

Gaster was reaching the edge of his patience when the King informed him of a new development, a human child had fallen to the Underground with its soul intact. King Asgore was going to extract all of the pain he could from the child after Gaster finished with it, and add the soul to his collection set aside in case the determination experiments proved fruitless.

It would only take fourteen souls to break the barrier from the inside after all.

Officially they now had two, or would once the new human child died. At this rate it would take half a dozen centuries, but the King would live that long now that his offspring had severed the line of lineage connecting them, and Gaster was a Skeleton. His race wasn't as possibly immortal as a Boss monster, but he was only in his prime and could look forward to two or three dozen more centuries.

Comparing the new soul to the old soul revealed some interesting facts, although the determination gleaned from it wasn't as powerful. For example the new soul was orange, while the first soul had been blue, perhaps indicating a different affinity between humans. When Gaster had extracted enough data and determination to start a new round of experiments, he returned the human child to King Asgore, informing the monarch that he might need access to the soul at a later date, but that for now there was no reason to keep a child in the labs.

The screams that echoed through the underground were enough to penetrate even into Gaster's lab, scaring Experiment one despite Gaster's reassurances that it was simply the King executing the human child.

Gaster couldn't understand why Experiment one had burst into tears at that explanation, although he supposed that it might have been a bad idea to leave it to supervise the child while he was beginning new batches of experiments.

He didn't see Experiment one for a few days, and he supposed the childlike thing was skulking. Gaster was reasonably surprised when it presented itself to him, demanding to help with the equations for the new batch of experiments. Intrigued by it's fascinating mind, and because none of the changes it proposed were variables he had gotten around to trying yet, Gaster allowed it.

Right about the time that the tube was set up with the new experiment, a young monster presented herself, demanding to be taken on for an apprenticeship. After testing her, Gaster allowed the little orange lizard to join him, although he was careful never to trust her with anything as delicate or irreplaceable as the human souls.

She learned to read hands fast enough, but she had discovered that experiment one wasn't limited to that form of communication, and set about teaching it words and concepts in English as well. Gaster found it easy enough to ignore the diversions between experiments.

Then experiment two was ready to pull from the tube.

* * *

Experiment one had somehow happened upon the correct variables to make a second viable experiment, and Gaster was nearly vibrating with excitement as he measured its power and health points. Once more, as with experiment one, the raw power was off the charts, though it didn't seem that much more potent than experiment one's. However Gaster was fairly excited about the fact that it's health points were as high as twenty. That meant that as it matured it would undoubtedly end up stronger and far less frail than its elder 'sibling'.

It took longer to become conscious than Experiment one, and Gaster found himself disappointed in it's lack of intelligence. It took longer to learn hands than the other, and longer still to learn to speak and read English. The lizard apprentice said that was normal in monster children, and Gaster found himself aghast at the very thought of it. How did any of the species survive to maturity if it took that long for them to learn the basics?

With another experiment in the tube, Gaster took his time testing the capabilities of the second one, and he wasn't as gentle as he had to be with experiment one.

That might have been a mistake. The apprentice didn't seem to have any attachment problems to the second experiment, but the first experiment showed distress every time Gaster performed any manner of invasive or painful procedures on the second.

Since the time had rolled around again, Gaster decided to take the first experiment out to hunt down the human husk that would come to the Underground this year.

While it proved to be an apt tracker, using magic and logic flawlessly to find its prey, it proved to be reluctant to kill the shambling husk.

Another monster got the kill and the EXP that came with it.

Gaster was highly disappointed, and soon measured experiment one's power levels again. It still wasn't enough to take down the Barrier, and he decided that perhaps it was time to find some way to dispose of the prototype. After all, while experiment two wasn't as intelligent or quick as one, it wouldn't take smarts or speed to take down the Barrier, only raw strength. Gaster broached the idea to the apprentice, who seemed shocked at the first suggestion, but soon came to accept the logic behind the decision.

It was Gaster's final decision.

* * *

One trembled as he looked at the dust that had been his creator, his father and mentor. It was early, or perhaps late, and Alphys wouldn't arrive for hours yet, but One knew he couldn't be here when she did. When Gaster made plans to dispose of him and reuse the parts for the base of a new experiment, Alphys hadn't objected. She had been upset, but not against the idea, and when One had spoken to her a short time after, she hadn't even tried to warn him.

One hadn't let on that he had overheard.

One had been making more and more trips outside the labs with Gaster and sometimes Alphys, and he understood a lot better now what it would take to survive the Underground. Hopefully he understood enough to bring Two with him, and keep Two safe.

The first thing they would need would be real names, like Alphys and Gaster had, but with those, One was certain he could get them somewhere safe, as far away from the capital as possible.


End file.
